Subsequent Events (Details) $ / shares in Units, $ in Thousands		1 Months Ended		3 Months Ended		9 Months Ended
	Nov. 03, 2020 USD ($)	Oct. 31, 2020 shares	Jul. 31, 2020 USD ($) shares	Sep. 30, 2020 USD ($) $ / shares	Sep. 30, 2019 USD ($) $ / shares	Sep. 30, 2020 USD ($) $ / shares	Sep. 30, 2019 USD ($) $ / shares	Nov. 02, 2020 number_of_properties	Sep. 30, 2020	Sep. 30, 2020 ft²	Jun. 29, 2020 USD ($)	Dec. 31, 2019 USD ($)	Jun. 29, 2019 USD ($)
Subsequent Event [Line Items]
Proceeds from Issuance of Preferred Stock and Preference Stock					$ 17,156		$ 46,765
Long-term Debt				$ 2,765,793		$ 2,765,793					$ 297,800	$ 2,567,022	$ 143,800
Common Stock, Dividends, Per Share, Declared | $ / shares				$ 0.175	$ 0.2625	$ 0.6125	$ 0.785
Number of units in real estate property									12,936	680		12,256
Subsequent Event [Member]
Subsequent Event [Line Items]
Proceeds from Issuance of Redeemable Preferred Stock			$ 2,800
Proceeds from Sale of Real Estate	$ 478,700
Subsequent Event [Member] | The Blake [Member]
Subsequent Event [Line Items]
Number of units in real estate property | number_of_properties								281
Series M Preferred Stock [Member] | Subsequent Event [Member]
Subsequent Event [Line Items]
Stock Redeemed or Called During Period, Shares | shares		862
Series M Preferred Stock [Member] | Subsequent Event [Member] | Unitsissued [Member]
Subsequent Event [Line Items]
Unitsissuedcumulative | shares			2,914
Proceeds from Issuance of Preferred Stock and Preference Stock			$ 12,600
Series A Preferred Stock [Member]
Subsequent Event [Line Items]
Proceeds from Issuance of Preferred Stock and Preference Stock					$ 116,828	$ 64,484	$ 369,420
Series A Preferred Stock [Member] | Subsequent Event [Member]
Subsequent Event [Line Items]
Stock Redeemed or Called During Period, Shares | shares		23,468
Series A Preferred Stock [Member] | Subsequent Event [Member] | Unitsissued [Member]
Subsequent Event [Line Items]
Unitsissuedcumulative | shares			13,986